van allen



(HoModaL) O; A. V-AN ALLEN. Device for Keeping the Pitmvaln of SewingMeehine off the Dead Centres. No. 229,021. Patented June 22,1880.

In Vania/ N.PETER5 PHOTO-UTHOGRAPHER. WASHINGTON, D C

UNITED STATES PATENT OFFICE.

CHARLES VAN ALLEN, OF ST. LOUIS, MISSOURI, ASSIGNOR OF ONE-HALF OF HIS RIGHT TO GABRIEL LONG, OF SAME PLACE.

DEVl CE FOR KEl-IPING THE PITMEN 0F SEWING-MACHINES OFF THE DEAD-CENTERS.

SPECIFICATION forming part of Letters Patent No. 229,021, dated June 22, 1880.

L Application filedApril 6,1880. (No model.)

To all whom it may concern Be it known that I, OHARLEs A. VAN ALLEN, of St. Louis, Missouri, having made a new and useful Improvement in Devices for Keeping the Pitman of a Sewing-Machine off the Dead- Oenters, of which the followingis a full, clear, and exact description, reference being had to the annexed drawings, making part of this specification, in which- Figure 1 is a vertical section taken through a sewing-machine having the improvement, only that portion of the machine necessary for illustrating the improvement being shown. Fig. 2 is a detail representation, being a view of the brake, the casing or shoe being in section; and Fig. 3 is a detail representation, being a view of the plate attached to the upper end of the pitman.

The same letters denote the same parts.

Devices have heretofore been employed in sewing-machines to prevent the pitman from stopping on the dead-centers; and my present aim is to provide an improved means therefor which is readily adjustable and adaptable to all the various styles of sewing-machines as are generally used.

It consists substantially as follows: A represents arod attached to and depending vertically from the table-top B. 0 represents the usual pitman. At its upper end it is furnished with a plate, D, having a series of perforations, d d d d. E represents a spring attached at one end to the plate D, and at the other end to a hook, F, that is arranged to be moved up and down on the rod A, and to be fastened at any point thereon by means of the set-screw f.

Thus arranged and connected, the spring acts to draw the pitman off the dead-centers and keep the machinery always in position for starting.

the outer end of the spring were always attached at the same level, the spring would not always act advantageously but by being able to slide the hook F up and down upon the rod A the spring can always be adjusted to draw in the right direction.

As the book, however, is moved up and down upon the rod A, it is evident that the distance between the hook and pitman O varies, affecting thereby the tension on the spring. To provide for this, and to enable the proper tension to be given to the spring, the perforations d d d d in the plate D are brought into use. As the hook is lowered on the rod A the inner end of the spring is moved correspondingly to perforations farther from the rod A, and as the hook is raised on the rod A the spring at its inner end is connected with the perforations nearer the rod A. In this way the spring can always be extended in the proper direction, and be strained to the proper degree of tension.

In some positions the spring E acts to draw the fly-wheel backward. This is undesirable so far as the sewing mechanism proper is concerned. At the same time it is desirable for the fly-wheel G to turn freely either backward or forward.

To accomplish both of these ends-that is, leave the fly-wheel free to turn either way and prevent any backward movement of the .needlea brake, H, is used inconnection tion with the fly-wheel, this portion of the improvement consisting in using the braking mechanism in connection with the hand-wheel, and also the meansfor drawing the pitman off the dead-centers.

When the hand-wheel is partly below the table-top B the brake H may be attached to the under side of the table-top.

I claim- 1. The combination of the table-top B, rod A, hook F, screw f, spring E, pitman 0, plate D, having the perforations d d d d, fly-Wheel O, and spring E, the latter being attached at G, and crank g, substantially as described. one end to the pitman and at the other end to 2. The combination of the table-top B, rod the hook F, substantially as described. A, sliding hook F, and spring E, substantially C. A. VAN ALLEN. 5 as described. Witnesses:

3. The combination of the hand-wheel I, CHAS. D. MOODY, brake H, belt J, fiy-whcel Gr, crank g, pitinan SAML. S. BOYD. 

